Effect Of Rho Kinase Inhibitor On Intestinal Injury In Septic Rats And Its Mechanism

Objective To explore the effect of Rhokinase inhibitor on intestinal injury in septic rats and its possible mechanism.Methods Thirty two healthy male Sprague-Dawley rats aged 6-8 weeks were selected and randomly divided into the following groups: sham-operation group（Sham group）,sham-operation + Y-27632 group（Sham + Y group）,sepsis group（Sepsis group）and sepsis + Y-27632 group（Sepsis + Y group）and with 8 rats in each group.Fifteen minutes before modeling,rats in Sham + Y group and Sepsis + Y group were intraperitoneally injected with Rhokinase inhibitor Y-27632 solution 5 mg/kg.While Sham group and Sepsis group were intraperitoneally injected with the same amount of PBS solution at the same time point.At 24 hours after the modeling,blood was obtained from the heart and was replicated to determine the serum diamine oxidase（DAO）level.Then the rats were euthanized to collect the small intestine tissue 2 cm from the ileocecal valve,the pathological changes of the intestinal tissue were observed under the light microscope after Hematoxylin-eosin（HE）staining,and Chiu’s score was performed.The expression of intestinal tissue Rho-related coiled-coil kinase 1（ROCK1）and nuclear factor-κB（NF-κB）protein were detected by immunohistochemistry.Enzyme-linked immunosorbent assay（ELISA）was used to detect the levels of tumor necrosis factor-α（TNF-α）and interleukin-10（IL-10）in intestinal tissue homogenate.Results The intestinal tissue structure of the Sham group and the Sham+Y group was intact and the mucosa was arranged neatly.Compared with Sham group,the intestinal mucosa of the Sepsis group was arranged disorderly,with epithelial cell necrosis and a large number of inflammatory cell infiltrations.Compared with the Sepsis group,the degree of necrosis of intestinal epithelial cells in the Sepsis + Y group was reduced,and a small amount of inflammatory cell infiltrations was seen.Compared with the Sham group,the intestinal Chiu’s score,the content of serum DAO,expressions of intestinal tissue ROKC1,NF-κB protein and level of intestinal homogenate TNF-αincreased,the level of intestinal homogenate IL-10 decreased in the Sepsis and Sepsis+Y groups（P <0.05）.Compared with the Sepsis group,the intestinal Chiu’s score,the content of serum DAO,expressions of intestinal tissue ROKC1,NF-κB protein and level of intestinal homogenate TNF-α decreased,while the level of intestinal homogenate IL-10 increased in the Sepsis+Y group.Statistically significant（P<0.05）.Conclusion Rhokinase inhibitor can reduce intestinal injury and improve intestinal permeability in septic rats.And its mechanism may be related to inhibiting RhoA/ROCK1/NF-κB signaling pathway and reducing intestinal inflammatory response.